1. the use of a word or phrase that merely repeats the meaning of another word or phrase in the same statement
Usage: linguistics; rhetoric
2. in taxonomy, the condition where a species name repeats the genus name
Usage: biology; taxonomy

Examples

• The phrase ‘free gift’ is an example of tautonymy since all gifts are inherently free.
• Saying ‘PIN number’ demonstrates tautonymy because PIN already means personal identification number.
• The biologist explained that Rattlesnake rattlesnake shows tautonymy in its scientific naming.
• Writers should avoid tautonymy to make their prose more concise and effective.
• The species Bubo bubo exemplifies tautonymy in zoological nomenclature.
• Her essay was criticized for excessive tautonymy and redundant phrasing.